CHAPTER 4 - MAINTENANCE & SPARE PARTS
22
87-900-045-01
(D)
4.1 GENERAL
Replacement HeliTests are available on an advance
exchange basis through sales offices.
4.2 CALIBRATION (CAL)
NOTE
Before starting the calibration sequence, move the
HeliTest and the probe away from Helium sources.
Whenever it is necessary to calibrate HeliTest after the
self test procedure, simultaneously press the SENS
and MODE pushbuttons for 2 seconds.
The display shows (fig. 4-1).
- - >
C a
l i b r a t i o n
P L E A S E W A I T
*
Figure 4-1
and after a few seconds the display will be as shown in
fig. 4-2.
❙❙❙❙
. . . . . . . . .
❙❙❙❙
0
< -
C A L
- >
*
Figure 4-2
Inserting in the probe a mixture sample of He/N
2
(50 - 1000 ppm of helium) and pressing SENS or
MODE (represented by two arrows).
it is possible to change the reading of the display until it
corresponds to the concentration of sampling gas.
Simultaneously pressing the SENS and MODE
pushbuttons, the new calibration coefficient is
memorized, and the HeliTest returns to the mode of
operation in which the calibration was started.